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arXiv · 1202.5769

Note on the Stabilities of the Light-like Galileon Solutions

Shuang-Yong Zhou
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Abstract

Light-like galileon solutions have been used to investigate the chronology problem in galileon-like theories, and in some cases may also be considered as solitons, evading a non-existence constraint from a zero-mode argument. Their stabilities have been analyzed via "local" approximation, which appears to suggest that all these light-like solutions are stable. We re-analyze the stability problem by solving the linear perturbation equation \emph{exactly}, and point out that the finite energy condition is essential for the light-like solitons to be stable. We also clarify potential ghost instabilities and why the zero-mode argument can not be naively generalized to include the light-like solitons.

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Shuang-Yong Zhou. 2014-06-27. Note on the Stabilities of the Light-like Galileon Solutions. https://doi.org/10.1103/physrevd.85.104005

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